introduction accurate estimation of the absorbed dose in radiosensitive organs, located away from the target volume during radiotherapy, is one of the main reasons for the development of reference phantoms. the international commission on radiological protection (icrp) reference phantoms can provide a more realistic view of the human anatomy in comparison with the previously used mathematical p...

background: treatment of ionizing radiation combined with chemical agents can enhance the inactivation of cells. the aim of this study was to determine the parameters involved in the inhibition of cell recovery. materials and methods: a mathematical model describing the process of recovery as a decrease in the effective radiation dose was used. the model includes two parameters, recovery consta...

the objective of this article is to analyze the data collected by the depart­ment of environmental health about the susceptibility of anopheles stephensi in the minab shahrestan to d.d.t. from 1957 to 1968, in order to: determine a mathematical model for the changes in l.d.50 by time and estimate the trend of l.d.50, for the future years. by plotting the changes in the resistance of the mosquit...

Environmental impact assessment (EIA) has led to the dominance of planners on the natural environment of the regions, providing the possibility of continuously monitoring and controlling the status quo by management staff. In this regard, a new semi-quantitative model is presented for the EIA of the Eastern Alborz Coal Mining complex using the matrix method, and determining the corresponding im...

Focusing on environmental impact assessment as a new tool to determine the harmful effects of projects on the environment is very necessary. The establishment of cement plants in Iran is accompanied by huge investments that aim to create jobs and have others economic aspects; this trend is on the rise. However, cement plants contribute to environmental pollutions. Therefore, understanding the e...

occurrence of chaotic behaviors because of fluctuations creation and their intensified transfer along the chain is one of the main causes of inefficiency of material requirements planning (mrp) based supply chains. one of the reasons of the inefficiency is the lumpiness phenomenon. through this phenomenon, some parts have an irregular production schedule, with nothing produced in some periods a...

Water vapour and ozone profiles in the midlatitude upper troposphere G. Vaughan, C. Cambridge, L. Dean, and A. W. Phillips Institute of Mathematical and Physical Sciences, University of Wales, Aberystwyth, UK Received: 16 September 2004 – Accepted: 8 October 2004 – Published: 15 December 2004 Correspondence to: G. Vaughan ([email protected]) © 2004 Author(s). This work is licensed under a Creative...